Electrical connecter



July 7, 1936. R. A. GOELLER ELECTRICAL CONNECTER Filed Aug. 6, 1931 IINVEN'II'OR Ro era /7- BY sma'wvihm.

u, ATTORNEY Patented July 7, 1936 UNITED STATES PATENT OFFICE ELECTRICAL CONNECTER.

Robert A. Goeller, New York, N. Y.

Application August 6, 1931, Serial No. 555,418

7 Claims. (Cl. 173-273) This invention relates to connecters particularly to electrical connecters commonly designated as cable taps which are employed for connecting the end of a branch conductor to a continuous electric cable.

Cable taps are customarily formed with two connected parts, one designed to clamp onto the end of the branch conductor and the other designed to embrace and clamp the main cable. The present invention relates more particularly to that part of the connecter which clamps onto the main cable and one object of the invention is to provide an improved clamping means which forms a firm electrical and mechanical connection with the cable.

Among the other objects of my invention are to provide a device of this character which is simple and economical in construction, strong and durable in use, which will not accidentally become loosened and which can be readily clamped to, or unclamped from the cable.

Other objects of my invention will appear from the following description taken in connection with the accompanying drawing which shows one embodiment of my invention and wherein:

Figure l is a perspective view of the cable tap,

Figure 2 is a perspective view of a yoke member forming part of the structure shown in Figure 1,

Figure 3 is a perspective view of the body member shown in Figure l, this member being shown ill as extending in the direction opposite to that shown in Figure 1 so as to illustrate more clearly its jaw or cable engaging surface,

Figure 4 is an enlarged central longitudinal sectional view of the structure shownin Figure l, partly an elevation, with the parts in position preparatory to clamping the connecter onto the main cable,

Figure 5 is a view similar to Figure 4 but showing a connecter tightly clamped onto the main cable, and

Figure 6 is a fragmentary view, similar to a portion of Figure 5 but showing a modified form of bolt and nut.

Referring to Figure l the connecter A serves to connect the end of the branch cable B with a continuous or main cable C. Cable B in the form of invention illustrated approaches cable C at.

claimed in my United States Patent Numbers 1,710,416, 1,712,108 and the details of this clamping means form no part of the present invention.

The clamping means F comprises a cylindrical body I ll formed at one end with serrated gripping surface or jaw ll adapted to cooperate with the similar surface or jaw l2, formed inside the bend v of the yoke member it, to grip the cable C in a manner shown in Figures 1 and 5.

The yoke it has extended sides 06 which as shown have outer and inner cylindrical surfaces and when the parts are assembled the body it fits between the sides It in contact with the inner cylindrical surfaces and the parts are held in this position by a bolt 20 and nut 2i. Bolt 20 is formed with a conical head 22 and nut it is also conical; both nut and bolt tapering inwardly as shown in Figures i and 5. Nut M is slotted outwardly from its inner end as indicated in Figure 5.

For receiving the bolt and nut the body it is formed with a transverse opening it tapered inwardly from its outer ends as indicated it, the

inclination of the walls at the taper corresponding to the inclination of the outer surfaces of the bolt head 22 and nut 2 l The tapered portions of the opening it are joined by a straight portion 2i which as will be noted from Figures 4 and 5, is of somewhat larger diameter than the shank 2B of the bolt 2t. Also the sides it of the yoke it are formed with inwardly tapering openings 3th the walls of which are inclined at the same angle as the outer surfaces of the bolt head and nut.

Figure l shows the position of the parts preparatory to clamping the connecter to the cable C. The yoke it has been placed over the cable, the body ill inserted between the sides of the yoke, the bolt till inserted through the openings it and 2d of the yoke and body respectively and the nut it screwed onto the bolt. Clamping of the connecter to the cable 0 is accomplished by tightening the nut on the bolt which has the effect of causing the jaws ill and i2 to approach one another and grip the cable C. In tightening the nut, the head 22 of the bolt and the nut ii act as wedge members pressing downward at their lower sides against the lower portion of the tapered surface of the openings till in the yoke and at their upper sides against the tapered walls of the opening it in the body. It is to be noted that the clamping forces are applied to the bolt head and nut and not to the shank of the bolt which floats freely in the central part of the opening it. The upward reaction thrust of the sides of the yoke against the nut and bolt head and the downward thrust of the body produce a. shearing rather than a bending strain and there is no bending of the bolt shank under the influence of these forces.

Pressure of the body and yoke against the slotted nut 2| causes the nut to bind tightly on the screw threaded shank of the bolt thus holding the parts rigidly in their set position. In practice I preferably employ screw threads for the nut and bolt of relatively low pitch and I find that with the parts constructed as disclosed, the connecter may be clamped to, or unclamped from, the cable C by turning either head 22 or nut 2| by a wrench. In other words the friction between the nut and bolt head, and the yoke and body is greater than the friction which opposes the turning of the nut on the bolt, with the result that the turning moment applied say to the bolt head results in the securing of the bolt and nut without the necessity of holding the nut during the screwing operation.

In practice the yoke, bolt and nut may be conveniently formed of copper alloy of relatively high strength and the body Ill which forms the main current conducting part, of copper. Due however to the relatively large area contact between the cylindrical body and the cylindrical inner faces of the side It of the yoke, the current path between the upper part of the cable C and the body, by way of the yoke M, is a path of relatively low resistance. It is to be noted that the shank of the bolt does not form a nec-= essary part of the electrical current.

It will be seen that the parts are of relatively simple construction and may be readily cast, turned and otherwise machined to shape. The yoke for example may be cast, the inner cylindrical surfaces of the sides l6 drilled or secured and the outer cylindrical surfaces turned. The openings 30 in the side l6 may then be drilled and reamed. The body and yoke may then be suitably assembled and while held in fixed assembled position, the jaws H and I! cut in a single operation. It is clear from the showing of the yoke and body in Figures 2 and 3, that I am not limited to a jaw of any particular size or shape and the jaw, if out round, may have a radius of curvature depending upon the size of the cable C to which the connecter is to be secured. If desired, the body and yoke parts in finished conditions, except for the jaws, may be kept in stock and jaws of the desired diameter cut as occasion arises.

In Figure 6, I show a modified form 01' bolt and nut for effecting the clamping action of the connecter to the main conductor. The form shown in Figure 6, which is preferably employed in the smaller sizes of connecters, comprises a bolt 20' which is provided with an outwardly tapering head 22 circular in section and having a slot 40 for operation by a screw driver. At the opposite end of the bolt is a tapered nut 2| which has a relatively deep slot H for reception of a screw driver for tightening or loosening the clamp. Slot 4i also serves the same purpose as slot 23 in the nut 2! namely to provide a locking or gripping action on the bolt when the nut is tightened.

While I have described my invention as applied to an electrical connecter or cable tap it is obvious that the invention may be applied to other forms of connecters such as pipe connecters and the like.

Having now described my invention what I claim and desire to secure by Letters Patent is:

1. In a connecter for attachment to a conductor, a body member having a jaw, a yoke embracing said body member and slidable with respect thereto, said yoke having a jaw adapted to cooperate with said first named jaw to grip the conductor, said yoke having inwardly tapering openings at opposite sides thereof and said body having an opening therethrough formed with inwardly tapering portions at its ends, a bolt extending loosely through said openings, said bolt having a conical head adapted to engage at one side the wall of one of said first openlugs and at the other side the wall of one of said tapered portions and a conical nut on said bolt adapted to engage at one side the wall of the other said first named openings and at the other side the wall of the other of said tapered portions.

2. In a connecter for attachment to a conductor, a body member having a jaw, a second I member embracing said body member and slidable with respect thereto, said second member having a jaw adapted to cooperate with said first named jaw to grip the conductor, said second member having inwardly tapered openings at opposite sides thereof and said body having an opening therethrough with inwardly tapering portions at its ends, a bolt having a conical head adapted to engage at one side the wall of one of said first named openings and at the other side the wall one of said tapered portions and a conical nut on said bolt adapted to engage at one side the wall of the other said first openings and at the other side the wall of the other of said tapered portions.

3. In a connecter for attachment to an object, a body member, a second member embracing said body member and slidable with respect thereto to clamp said connecter to said object, said second member having inwardly tapering openings v at opposite sides thereof and said body having named first openings and at the other side the i wall of the other of said tapered portions.

4. In a connecter for attachment to a conductor, a body member having a jaw, a second member embracing said body member and slidable with respect thereto, said second member having a jaw adapted to cooperate with said first named jaw to grip the conductor, said second member having inwardly tapering openings at opposite sides thereof and said body having an opening therethrough formed with inwardly tapering portions at its ends, a threaded bolt extending through said openings, said bolt having a conical head adapted to engage at one side the wall of one of said first named openings and at the other side the wall of one of said tapered portions, means on said bolt having a conical face adapted to engage at one side the wall of the other of said first named openings and at the other side the wall of the other of said tapered portions and having screw threads engaging the threads of said bolt for drawing said head and said face toward one another thereby moving the jaws to clamp the conductor.

5. In a connecter, two members slidable with respect to one another and each having a clamped 75 aocaeie if t jaw, said members being formed with abruptly tapered openings arranged end to end, a rotary screw wedge having a taper corresponding to the taper of said openings, said wedge engaging on one side the wall of one of said openings and the other side the wall of the other opening and being adapted on rotation to move in a direction through said openings to cause said jaws to move toward one another and subject said wedge to a shearing stress.

6. In a connecter for attachment to an object, a body member having a jaw, a second member embracing said body member and slidable with respect thereto, said second member having a jaw adapted to co-operate with said first named jaw to grip the object, said second member having inwardly tapering openings at opposite sides thereof and said body having an opening therethrough formed with inwardly tapering portions at its ends, a threaded member extending through said openings and clamping means having conical faces at opposite ends of said threaded member, one of said faces being adapted to engage at one side the wall of one of said first named openings and at the other side the wall of one of said tapered portions and the other face being adapted to engage at one side the other of said first named openings and at the other side the wall of the other of said tapered portions and said clamping means having screw threads engaging the threads of said rod for drawing said faces toward one another through the openings to cause the jaws to move to clamp an object.

7. In a connecter, two members slidable with respect to one another, each having a clamping jaw and each formed at opposite sides with tapered openings, the two openings in the respective members at each side being arranged end to end, wedges at opposite sides, each wedge extending into the two openings at its corresponding side and each wedgeengaging at one side of the wedge the wall of one opening and at the opposite side of the wedge the wall of the adjacent opening, means extending between the wedges for forcing them through their respective openings whereby said jaws are caused to move toward one another and said wedges are subject to shearing instead of binding strains, said means being substantially free of said members whereby movement of said members by said wedges does not subject said means to bending strains.

ROBERT A. GOELLER 

